Huge generators would operate in waters over a thousand feet deep.

The US and UK last week announced plans to develop enormous floating offshore wind turbines that can be deployed in much deeper waters and further out to sea.

By being freed of the towers that would usually tether offshore wind turbines to the seabed, floating turbines are not restricted to the usual 60-meter (200-foot) depth limit, and instead can be located in waters several hundred meters deep. Not only does this increase the areas of sea and ocean that can be harvested for wind, it grants access to faster and more reliable winds. And because wind turbines can be located further from the coast, they can be positioned beyond the sight of inland communities that may be less than impressed by the insertion of a wind farm into their scenic coastal view.

Last week Energy Ministers from the world's 23 largest economies met in London at the Clean Energy Ministerial co-chaired by US and UK Energy Secretaries Steven Chu and Edward Davey. In a statement issued ahead of the event, Davey announced that both the US and UK would be "making funding available," and described the two countries as being "determined to work together to capitalise on this shared intent."

Though couched in rather vague language, the statement does go into more detail as to the funding available. The UK's Energy Technologies Institute (ETI) is currently commissioning a £25 million ($41 million) floating demonstrator project. Selected participants will be invited to submit concepts of a floating wind turbine between 5 and 7 megawatts (MW) capacity. The winner will be asked to produce a working prototype to be installed by 2016. In the meantime, the ETI is narrowing down sites that could host the demonstrator. The additional waters opened up by floating wind technology allow access to hundreds of of gigawatts of additional wind resources. The UK's offshore wind potential has been calculated at 2200GW, which is thought to be about a third of Europe's total.

Meanwhile, the US Department of Energy has announced a $180 million "funding opportunity" for four offshore wind demonstration projects, though none is explicitly allocated for floating wind technology. Despite an estimated 4150GW of offshore wind potential, the US has no offshore wind infrastructure as yet, and floating technology may further the cause if NIMBYists can be persuaded that turbines will be placed out of sight and earshot.

Though floating wind turbines do exist, the cautious research-led approach adopted by the US and UK makes sense when you look at the scale of the task they've taken on. Wind turbines over 5MW in capacity are enormous: Enercon's 7.5MW E-126 inland turbine has a rotor diameter of 126 meters (413 feet).

To date, the largest floating wind turbine that has been installed is Norway's 2.3MW Hywind which has a rotor diameter of 82 meters (270 feet). The fact that its development cost is $62 million raises questions about whether the investment earmarked by the US and the UK will be enough to produce a stable floating turbine with more than double that capacity.

The form that the potential floating turbines will take hasn't been decided, but the most likely design is that individual turbines will effectively form vertical spar buoys, each moored by several catenary cables weighted at the ends. This would effectively be an enlarged version of the system used to moor the Hywind turbines—which actually employs additional 60-ton weights at the middle of each catenary cable in order to provide extra tension. Indeed, the next stage of the Hywind project hopes to apply the principle to a 5MW turbine in waters 320 meters (1,000 feet) deep—Norway has large-scale floating wind ambitions too.

An alternative means of mooring would be to adopt a tension-leg system, commonly used on offshore oil platforms since the 1980s. Something like an inverted pendulum, a tension-leg system would see a turbine mounted on a highly buoyant platform with steel tendons stretching vertically down to the sea bed. Research by MIT and the National Renewable Energy Laboratory suggests that 5MW turbines should be feasible at depths of up to 200 meters (650 feet).

The idea of multiturbine pontoons has additionally been, er, floated, but there are fundamental concerns about the cost of such systems, as well as their ability to withstand the extreme forces floating wind turbines would face during extreme weather.

Offshore wind plans are by no means restricted to the US and Europe. The Fukushima Recovery Floating Wind Farm Pilot Project confirmed by the Japanese government last month will initially consist of a 2MW turbine, to be joined by two 7MW turbines by 2016. And by 2020 the Marubeni Corporation plans to build a 1GW floating wind installation off Japan's northern coast, partly funded by the country's tsunami recovery budget. If it goes ahead, the scale of the wind farm would eclipse any sort of offshore wind farm currently in existence or under construction, though much bigger installations are in development, including a 9GW offshore farm at Dogger Bank off England's east coast.

James Holloway
James is a contributing science writer. He's a graduate of the Open University, with a B.Sc. in Technology and a Diploma in Design and Innovation. Twitter@jamesholloway

Fox news reported that these things add to the global warming issue–a problem they have flat out denied in the past. My small brain doesn't know what to think about this. Wouldn't it be better to set up deep sea drilling that have a much higher safety rating than these turbines and a reduced environmental impact?

For those of you with an eye to historical detail, please note that the apportionment of ocean resources will occur in our lifetime. Already many fish stocks are overexploited, eventually a structure will need to be in place, and it will most likely be geographic.

This is an interesting research project, but these things will be expensive. I'd rather have them 4 miles off shore in shallow water, and see the tiny turbines on the horizon, than pay more to push them out of view. Current off-shore wind turbine technology is already way more expensive than wind turbines on land.

They would use subsea DC cables from an offshore substation for these floaters. AC cables can be used for short distances, but it sounds like these would typically be way out there.

SgtCupCake wrote:

Fox news reported that these things add to the global warming issue–a problem they have flat out denied in the past. My small brain doesn't know what to think about this. Wouldn't it be better to set up deep sea drilling that have a much higher safety rating than these turbines and a reduced environmental impact?

I'd like to reply, but you can't seem to write a coherent thought for me to really understand you. Are you saying that deep sea oil drilling and offshore wind turbines are mutually exclusive? Are you saying that wind turbines are unsafe? Which ones, the ones they are trying to invent with this funding? Are you saying that floating offshore wind turbines add to global warming, or to the global warming ISSUE?

This is an interesting research project, but these things will be expensive. I'd rather have them 4 miles off shore in shallow water, and see the tiny turbines on the horizon, than pay more to push them out of view. Current off-shore wind turbine technology is already way more expensive than wind turbines on land.

They would use subsea DC cables from an offshore substation for these floaters. AC cables can be used for short distances, but it sounds like these would typically be way out there.

There is a strategic use. As the population riots inland, there will be handy charging stations available at sea for the government and the rich elite.

Interesting. The obvious environmental concern would be for seabirds like petrels and albatross. On the other hand, you can bet your bottom dollar that these floating wind farms would displace fishing activities like trawling and drift nets from their vicinity. That would make them something like defacto marine reserves with sufficient economic and security implications to ensure a high level of enforcement in keeping fishermen from illegally targetting the 'reserve' as is commonly the case in many marine reserves today. Depending on where these are placed, this could be a good thing from a fisheries conservation point of view.

Interesting. The obvious environmental concern would be for seabirds like petrels and albatross. On the other hand, you can bet your bottom dollar that these floating wind farms would displace fishing activities like trawling and drift nets from their vicinity. That would make them something like defacto marine reserves with sufficient economic and security implications to ensure a high level of enforcement in keeping fishermen from illegally targetting the 'reserve' as is commonly the case in many marine reserves today. Depending on where these are placed, this could be a good thing from a fisheries conservation point of view.

These exact discussions are taking place in North Carolina. Sections of ocean used by military, shipping, and fishing are being marked off the list of available offshore wind sites.

For those of you with an eye to historical detail, please note that the apportionment of ocean resources will occur in our lifetime. Already many fish stocks are overexploited, eventually a structure will need to be in place, and it will most likely be geographic.

You think as I do. All the sudden we've got a feasible excuse for an ocean grab. "This is US sovreign territory which extends our borders to HERE!"

So, what happens when a ship manages to somehow collide into one of these?

Fox news reported that these things add to the global warming issue–a problem they have flat out denied in the past. My small brain doesn't know what to think about this. Wouldn't it be better to set up deep sea drilling that have a much higher safety rating than these turbines and a reduced environmental impact?

If so, their statement would be very misleading. All the above article says is that the air close to the surface is slightly warmer at night because the cooler air higher up in the atmosphere can't circulate as easily to equalize the temperature. The overall temperature of the Earth is the same, the heat is just distributed differently.

Studies have shown that people who rely primarily on Fox News are actually less likely to know the facts about sensitive issues than people who watch no news at all. Probably because of distortions like that.

Interesting. The obvious environmental concern would be for seabirds like petrels and albatross.

In many places environmental assessments on bird and bat populations are required for construction of new wind farms, and there have been several studies on this topic though the conclusions are still up for grabs. The general consensus seems to be that the habitat disturbance due to the presence, construction and maintenance of the farm will cause more harm than direct collisions with the towers. Making sure that wind farms are not placed near critical nesting habitat or migratory pathways is considered best practice right now (which might seem like common sense from a biology standpoint). There is a fair amount of information out there, even on Google, if you are interested.

This might sound like a stupid question but I'll ask anyways. I understand physics, but not how the environment work, or power generators, or weather, etc, etc.

There is no such thing as a free lunch, and what I mean by that in this context is energy is only ever converted, not created (conservation of energy) Wind generators simply take the energy from moving air particles and converts them to electricity, to do so the air particles slow down. Knowing that, I wonder what the impact would be of, essentially, slowing the wind down?

And on a similar note, why not use generators in places where we don't want the energy, where we instead erect barriers instead? Like ocean waves that are eroding cliff sides, why not employ tidal wave generators so the waves impact with less energy? or dissipate heat instead of trying to convert it back to energy (since heat is energy)? Is it just to cost prohibitive to capture the energy instead of blocking it?

These wind turbines are actually giant sacrificial fans from which the incarnation of Baal will use to throw humans into upon his return on December 21st. The U.S. government knows this and is placing the devices several miles offshore so when the killing begins it will not be observed and reported by the news media. Once the fans ramp up to true operating speed they will pulverize humans and turn them into mist as our demonic lord Baal throws his victims in and smiles with satisfaction at the red vortices exhausting the remains of the damned. May he keep you in his hand and close his fist upon you, the worm that you are.

For those of you with an eye to historical detail, please note that the apportionment of ocean resources will occur in our lifetime. Already many fish stocks are overexploited, eventually a structure will need to be in place, and it will most likely be geographic.

Amen brother.

The only way to terminate the overexploitation of the oceans is for the seas to be divvied up to the states of the world. These governments can then lease or sell the the use rights to private actors who will care for the resource.

The apportionment is very much needed, and the sooner it gets implemented, the better.

Fox news reported that these things add to the global warming issue–a problem they have flat out denied in the past. My small brain doesn't know what to think about this. Wouldn't it be better to set up deep sea drilling that have a much higher safety rating than these turbines and a reduced environmental impact?

I'd like to reply, but you can't seem to write a coherent thought for me to really understand you. Are you saying that deep sea oil drilling and offshore wind turbines are mutually exclusive? Are you saying that wind turbines are unsafe? Which ones, the ones they are trying to invent with this funding? Are you saying that floating offshore wind turbines add to global warming, or to the global warming ISSUE?

That was a bit aggressive. He said that Fox news claimed that wind turbines contribute to climate change; climate change is something that Fox news is somewhat notorious for outright denying. Ergo, Fox news can't keep their story straight.

Regarding drilling vs turbines, Sgt: Drilling requires something to drill to, so it's more location-dependent than wind turbines. Further, planet-bound petroleum is a finite resource, whereas the kinetic energy of wind derives from solar, making it effectively infinite. So as whquaint pointed out, while they are not mutually exclusive, the point here is to get the new tech rolling. Your suggestion that it's better to stick with off-shore drilling is akin to suggesting that these new-fangled automobiles are unproven and dangerous and we should stick with horses.

Eider wrote:

craigdolphin wrote:

Interesting. The obvious environmental concern would be for seabirds like petrels and albatross.

In many places environmental assessments on bird and bat populations are required for construction of new wind farms, and there have been several studies on this topic though the conclusions are still up for grabs. The general consensus seems to be that the habitat disturbance due to the presence, construction and maintenance of the farm will cause more harm than direct collisions with the towers. Making sure that wind farms are not placed near critical nesting habitat or migratory pathways is considered best practice right now (which might seem like common sense from a biology standpoint). There is a fair amount of information out there, even on Google, if you are interested.

While that seems wise, wouldn't chicken wire or something similar prevent the majority of the direct collisions, without significantly reducing the airflow? Can't hurt to prevent those, even if they're not as harmful.

These wind turbines are actually giant sacrificial fans from which the incarnation of Baal will use to throw humans into upon his return on December 21st. The U.S. government knows this and is placing the devices several miles offshore so when the killing begins it will not be observed and reported by the news media. Once the fans ramp up to true operating speed they will pulverize humans and turn them into mist as our demonic lord Baal throws his victims in and smiles with satisfaction at the red vortices exhausting the remains of the damned. May he keep you in his hand and close his fist upon you, the worm that you are.

Nice try, sockpuppet. Next time don't choose your own name as your online handle.

I can see it now, migrating birds see a giant island while crossing the Atlantic and decide to take a pit stop. Carnage ensues. It's like a bird magnet.

It would probably be "carnage" the first year or two. But as the smarter birds avoid the rather obvious blade thingys they will survive and produce smart offspring as well. Behold, evolution in action.

These wind turbines are actually giant sacrificial fans from which the incarnation of Baal will use to throw humans into upon his return on December 21st. The U.S. government knows this and is placing the devices several miles offshore so when the killing begins it will not be observed and reported by the news media. Once the fans ramp up to true operating speed they will pulverize humans and turn them into mist as our demonic lord Baal throws his victims in and smiles with satisfaction at the red vortices exhausting the remains of the damned. May he keep you in his hand and close his fist upon you, the worm that you are.

Nice try, sockpuppet. Next time don't choose your own name as your online handle.

I don't see any mention of how they plan to get the power from the turbines to land.

Um... cables?

Saying "cables" is all well and good. But are they cables dropping down a thousand feet and then following the seafloor to land? Are the shallow cables floating just deep enough to hopefully not get cut by passing boats? What happens to these cables in bad weather? When the towers are floating, the dynamics are different, and inquiring minds want to know the details.

There is no such thing as a free lunch, and what I mean by that in this context is energy is only ever converted, not created (conservation of energy) Wind generators simply take the energy from moving air particles and converts them to electricity, to do so the air particles slow down. Knowing that, I wonder what the impact would be of, essentially, slowing the wind down?

And on a similar note, why not use generators in places where we don't want the energy, where we instead erect barriers instead? Like ocean waves that are eroding cliff sides, why not employ tidal wave generators so the waves impact with less energy? or dissipate heat instead of trying to convert it back to energy (since heat is energy)? Is it just to cost prohibitive to capture the energy instead of blocking it?

Yes, but the air moves basically because of the sun. The sun has a LOT of energy reserves. for what it would do to slow down the air. I don't know. The earth is a vast place, and I doubt putting up some turbines will slow it down appreciably. It's also a very inneficient process, but one that is more-or less free (if you can build the turbines cheaply). Meaning, the turbine takes a very small percentage of the energy required to move air. I mean, think of how large the atmosphere is... 40 miles in places? larger? we have some devices that are extracting just a portion of the energy from a miniscule portion of the earth surface + 200 or so feet. That is *tiny*, even if we were to blanket the costal areas of the ocean with turbines. That is my initial take on it.

Also afaik, it's more expensive to harness tidal forces. there are ideas on how to do it more effectively, but they are very expensive. Wind turbines are here now.

I'm sure wikipedia has decent articles on wind vs tidal, if you are interested.

As for slowing down the wind to any appreciable degree, I'm not sure I've ever read anything on that before.

I don't see any mention of how they plan to get the power from the turbines to land.

Um... cables?

Saying "cables" is all well and good. But are they cables dropping down a thousand feet and then following the seafloor to land? Are the shallow cables floating just deep enough to hopefully not get cut by passing boats? What happens to these cables in bad weather? When the towers are floating, the dynamics are different, and inquiring minds want to know the details.

Are you saying that all liberals are NIMBY? If not, what percentage? Are any non-liberals NIMBY?

I'll stand up: I'm a liberal - and I live less than 20 miles from SMUD's (Sacramento power) abandoned Rancho Seco nuclear plant. It ran from 1975 to 1989 (shut due to vote, spearheaded by scaremongers). I'm all for revamping it - cheaper than building a new one from scratch.

So, yes, I don't mind the idea of living near a nuclear power plant, even though I'm a liberal; I fully support the resource.

I can see it now, migrating birds see a giant island while crossing the Atlantic and decide to take a pit stop. Carnage ensues. It's like a bird magnet.

Seems to me that birds landing on the base would be pretty safe. The blades are much higher than the base.

I was mostly joking. I have no idea if it would have a significant impact or not. But if birds are hit by these things all the time while flying around land or near land (where they have plenty of places to land and rest) then I have to believe they will be attracted to these as a place to rest and get hit while coming in for the landing.

i still dont fully understand why we dont just go full on nuclear... this wind/solar stuff is ridiculous

Simply put, NIMBYists are more frothy mouthed over radioactive waste than noisy wind turbines. Not to mention more people turn into NIMBYists over radioactive waste. Find an inexpensive way to remove radioactive wastes from the planet and you'll make most people happy.

Except for the ones who will tell you that by jettisoning it into the sun, we'll irreparably damage our sun and the sun will turn against us and blow us up/irradiate us/implode and leave us in the cold. (modify said argument for whatever solution is found)

Bottom line for any energy source is waste. Whether it's heat generated, currents altered, pollutants of whatever nature, etc. It's all about the waste product and how someone, somewhere, is going to find it worse than the alternative.

Now, if we can find ways of taking the waste and putting it to use (ie, heat displacement utilized to warm a home or a greenhouse or a swimming pool, etc) then we're a step ahead of the game.

With nuclear material, there's really nothing you can do with the waste product, other than store it somewhere and watch the half-life burn off over many years. If we could utilize it in some way shape or form, all the way up to the point where it's really a negligible health hazard, then we could look at nuclear energy as a full on solution.